Study on Shigella Detection by ATP Bioluminescence Magnetic Enzyme Immunoassay

[Objective] The research aimed to establish a rapid detection method for Shigella. [Method] Combining immunomagnetic separation technology with ATP bioluminescence technology, a new kind of fast and accurate ATP bioluminescence magnetic enzyme immunoassay technique for Shigella was established. [Result] Using ATP bioluminescence magnetic enzyme immunoassay technique to detect standard solution for Shigella （ATCC 25931 ）, result showed that correlation coefficient between relative light intensity detected by instrument and bacteria concentration detec- ted by culture counting method was 0.981 1. Moreover, relation curve between relative light intensity and Shigella concentration was drawn. [ Conclusion] The method had a high detection speed and accuracy, and could be used for the rapid detection of pathogen in food and environment.

Application value of ATP based bioluminescence tumor chemosensitivity assay in the chemotherapy for hydrothorax caused by non-small cell lung cancer

Objective： The aim of the study was to investigate the clinical value and application of ATP based bioluminescence tumor chemosensitivity assay （ATP-TCA） in the chemotherapy for hydrothorax caused by non-small cell lung cancer （NSCLC）. Methods： Hydrothorax specimens from 120 NSCLC patients were analyzed by ATP-TCA and the most sensitive chemotherapeutic drugs were used in NSCLC patients （treatment group）. At the same time, 56 NSCLC patients with hydrethorax were admitted in our Hospital （Department of Oncology, The No. 2 People＇s Hospital of Yibin, China） and given chemotherapy without guidance of the ATP-TCA （control group）. Before the third chemotherapeutic cycle, clinical outcomes were analyzed in the two groups. Results： Effective rate of hydrothorax in treatment group was 67%, while 46% in control group （P 〈 0.05）. In refractory hydrothorax patients, they were 69% and 40% （P 〈 0.05）, respectively.In vitro results correlated well with clinical outcomes （P 〈 0.01）. Conclusion： Effective rate of chemotherapy for hydrothorax in NSCLC is higher in treatment group than that in control group. ATP-TCA is especially helpful for refractory hydrothorax.

Preparation of recombinant firefly luciferase by a simple and rapid expression and purification method and its application in bacterial detection

A simple and rapid expression and purification method of recombinant firefly luciferase was developed for bacteria detection. A modified luciferase gene from North American firefly Photinus pyralis was cloned into pET28a expression vector and the recombinant protein was produced in Escherichia coli BL21. The recombinant luciferase,equipped with a polyhistidine affinity tag,was purified by immobilized metal ion affinity chromatography (IMAC). The approach generated an abundant expression and an efficient purification of a recombinant luciferase with final yield 1.995mg/L of cell culture. Experiments on the recombinant luciferase also showed that the relative light units (RUL) of the enzyme were 5.8×108,and the specific activity was 2.9×1010 RLU/mg. By applying adenosine triphosphate (ATP) bioluminescence to detection of the coin bacteria using the recombinant protein,the ATP content of bacteria was 9.48×10-16mol/mL,and was identical to the bacteria counts (4500CFU/mL) in order of magnitude. Taken together,our results provided a simple and efficacious method of the preparation of recombinant luciferase,which could be applied in the determination of bacteria via ATP bioluminescence.